Redirect DNS requests to more than 1 IP

RouterOS General
1

Hello,
I created these 2 rules on my Mikrotik:

:ip firewall nat add chain=dstnat action=dst-nat to-addresses=PRIMARYDNS to-ports=53 protocol=udp in-interface=bridge1 dst-port=53
:ip firewall nat add chain=dstnat action=dst-nat to-addresses=PRIMARYDNS to-ports=53 protocol=tcp in-interface=bridge1 dst-port=53

where PRIMARYDNS is my first DNS. In this way I can redirect all DNS traffics to the PRIMARYDNS Server
So, is it possible to create other 2 rules, equals to the previous ones, except for the field to-address that will become SECONDARYDNS, so that if the first DNS (PRIMARYDNS) should have problems after a few attempts automatically switch to the secondary ones (SECONDARYDNS).

In short, it would be like having a secondary DNS to redirect traffic.

Thanks,
Marco

2

what is the purpose of the 2nd DNS ?

3

Hello Adahi,
Thanks for the reply.
I need the second DNS as backup so that if the first one is down automatically all dns requests will redirect to the second DNS.

Thanks,
With best reagards,

Marco

4

use anycast DNS service instead ex: 8.8.8.8

5

Hi,
No because i need to use only my DNSs and I have more than one external Server DNS.

Thanks,
With best regards,

Marco

6

this may help you

{
:local dns1 8.8.8.8 
:local dns2 9.9.9.9 

/tool netwatch
add down-script="/ip firewall nat disable numbers=[find to-addresses=$dns1];\r\
    \n/ip firewall nat enable numbers=[find to-addresses=$dns2];" host=$dns1 up-script=\
    "/ip firewall nat enable numbers=[find to-addresses=$dns1];\r\
    \n/ip firewall nat disable numbers=[find to-addresses=$dns2];"
}
7

You can direct all DNS requests incoming on your local network to the IP address of the router itself (on your local network) and then setup
the internal DNS service with the IP addresses of the external servers you want to use.
The router automatically uses the specified DNS servers (in /ip dns) as available. It also caches the requests.